Setup

This project requires at least the most recent Java release, at times even early-access builds of upcoming versions.
You can get OpenJDK builds for both from jdk.java.net.

Most of the project can be built with Maven.
It uses toolchains to configure which Java version Maven should use for compilation and packaging.
Create/modify toolchains.xml in Maven's user folder (~/.m2 on Linux) to contain a block like the following:

If your IDE doesn't like new syntax or APIs, you can always compile and run by hand - see compile.sh, run.sh (which expects the fully qualified name of the main class as argument) and compile-run.sh (conveniently combines the two - aso needs the main class).
The scripts are written for Linux but should look similar on other operating systems.
If the approprate Java verson is not on your path, configure it in executables.sh.

For some features, you have to run the .sh scripts in the root directory.
If that's necessary, the feature list below mentions it.